Piston with a controlled expansion piston anti-extrusion ring
US4516785A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1982 |
| Grant date | May 14, 1985 |
| Priority date | — |
| Expiry date | Dec 10, 2002 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J15/166
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
In a pump for pumping fluid having a piston with a flange, a cylinder, a gap between the cylinder and the flange, and a sealing device, an improved sealing device has an anti-extrusion ring located at a face of the sealing device opposite the fluid. The anti-extrusion ring is bonded to the sealing device and is biased to be in intimate, movable contact with the cylinder. The anti-extrusion ring is made from a material having a modulus of elasticity sufficient so that it does not extrude into the gap under the influence of the hydrostatic pressure generated during pump operation. The sealing device, or a portion thereof, has a modulus of elasticity sufficient to control the radially outward expansion of the anti-extrusion ring so that the sides of the ring do not press too tightly against and cause excessive wear of the cylinder. The anti-extrusion ring has at least one split in it, and a ring having a number of tangential-cut splits or step-cut splits could be used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.